Perinephric Hematoma in Dengue Fever

Introduction: Dengue is a mosquito-borne infection that presents with a wide spectrum of symptoms, including fever, multi-organ failure, dengue hemorrhagic fever, and shock. Acute kidney injury (AKI) is commonly reported with dengue. We are presenting a unique presentation of dengue hemorrhagic fever and AKI. Case Description: A 24-year-old man with a history of epilepsy, autism, and diabetes, presented with persistent fever with Tmax 104.4 F eleven days after returning from the Dominican Republic. On day 5 of admission, he developed stage III AKI (Cr increased from 0.7mg/dL baseline to 6.5mg/dL). At this time, our differential included acute tubular injury (ATI), glomerulonephritis, and DRESS syndrome. Other labs were significant for thrombocytopenia, elevated AST/ALT, CK 1017U/L, and haptoglobin 340mg/dL. Serologies showed elevated C3/C4 and negative ANA, dsDNA, and ANCA. Urine microscopy showed granular casts. On day 6, he acutely developed significant abdominal pain and CT abdomen/pelvis revealed a 7.6x6.9x8.3 cm left perinephric hematoma (hemoglobin declined from 11.6mg/dL on admission to 9.5mg/dL). Page kidney was suspected when he developed hypertension, and he was started on captopril. However, his kidney function continued to worsen and he ultimately required dialysis for refractory hyperkalemia. Infectious workup showed dengue IgM 10.15 and IgG 6.95. His course was complicated by secondary HLH (ferritin > 16,000; positive soluble IL-2R and CXCL9) and he was given a course of methylprednisolone. On day 13, the patient defervesced and started to show kidney recovery. Dialysis treatments were discontinued and steroids were tapered. Serum Cr was 1.3mg/dL on discharge and 1mg/dL two weeks later. Discussion: Dengue can trigger AKI through several proposed mechanisms including rhabdomyolysis, immune complex mediated glomerular damage, hemolytic uremic syndrome, cytokine storm, and bleeding diathesis (mucosal, intramuscular, retroperitoneal bleeding have been reported). While the cause of AKI in this patient is likely multifactorial, the perinephric hematoma (“page kidney”) is a novel manifestation of dengue hemorrhagic fever. Page kidney results from the external compression of the kidney by subcapsular hematoma and can result in renin-angiotensin system activation, leading to hypertension.